Sewing machine



May 3, 1955 F. sENGsTocK 2,707,447

SEWING MACHINE 'Filed Inlay 21, 1952 2 Sheets-Sheet l e au M 45 @i l `oZ l l 49 l, 33

May 3, 1955 F. sENGsTocK 2,707,447

SEWING MACHINE Filed lay 21 1952 I 2 Sheets-Sheet 2 :llllllll- INI/NTOR.F fea/wr f/vasroC/f United States Patent O SEWING MACHINE FriedrichSengstock, Biebernhem, Germany, assignor of fifty per cent to BernhardSengstoek, Brooklyn, N. Y.

Application May 21, 1952, Serial No. 289,176 7 Claims. (Cl. 112-1S4) Thepresent invention relates to stitching and sewing machines for textiles,and particularly to a special table sewing machine.

The main object of our invention is to provide a table sewing machinethat is exceptionally capacious and versatile in utility for sewing allkinds of textiles with ease.

Another object is to provide such a sewing machine that has such anadvantageous construction that a more free manipulation of the fabricbeing sewn is possible than is usually the case on conventionalmachines.

A further object is to have such a sewing machine provided with anespecially simple drive mechanism that facilitates operation of themachine as a whole.

It is also an object of our invention to include in the construction ofour sewing machine a special housing or frame that is particularlyadvantageous to allow inclusion of the special simple drive mechanismand provide ample space for voluminous fabrics and articles to be sewnin order to impart an especially wide field of operation to the machine.

Yet another object is to have such a sewing machine that contains themain portion of the drive within a compact drive housing that extendsupward a limited distance and provides the sewing zone upon the top ofthe same, thus avoiding the necessity for a stand or the like forthemachine, to contain any part of its mechanism.

A practical object is, of course to provide a table sewing machine thatis simple to make and as simple to use, as well as virtually portableand reasonable in cost.

Other objects and advantages of our invention will appear in greaterdetail as the specification proceeds.

In order to facilitate ready comprehension of this invention for aproper appreciation of the salient features of the same, the inventionis illustrated on the accompanying drawings forming part hereof, and inwhich:

Figure l is a side elevation of a table sewing machine made according tothe invention and embodying the same in a practical form, the View beingpartly in section;

Figure 2 is an enlarged vertical section of the lower left housing ofFigure l disclosing details of construction;

Figure 3 is a top plan view of the same mechanism housing of Figure 2;and

Figure 4 is an enlarged top plan View of the thread carrier and spool ofthe machine of Figures l, 2 and 3.

Throughout the views, the same reference numerals indicate the same orlike parts and features.

Upon conventional sewing machines, certain limitations are always inevidence, such as a narrow throat or space for the textiles to be sewn,due to the nature of the mechanism of such machines, and also, below thesewing zone, the machines of conventional type require to have theshuttle mechanism depressed into a stand top or table of some kind, anda motor drive, if used i`s substantially always an exposed feature asthough it were an after thought.

Upon considering this problem, it has occurred to us that a sewingmachine should have a large space for handling the goods to be sewn andshould also have its mechanism designed to be located within a compacthousing and avoid having too much mechanism` requiring a sewing head. Asa result, we have succeeded in producing a special table sewing machineas already outlined, which we shall now proceed to describe in detail inthe following,

Hence, in the practice of our invention, and referring also again to thedrawings, an elongated base 1 is adapted to be placed upon a table orother support, and at the one end has an arcuate hollow arm 2 extendingupwardly therefrom and arching over and down toward the other end of thehase. At the latter end, the base is provided with a special housing 3which may be more or less cylindrical in outline and having a pair ofsubstantially horizontal or level fabric feeders 4, while above thesefeeders, the arm 2 terminates in a depending end S. The space betweenthe end 5 of arm 2 and the top of housing 3 above feeders d may betermed the sewing zone, as will be further referred to later on.

Within the mentioned housing is mounted an electric motor 6 that servesto drive the machine as a whole, ln the bottom of the housing 3 andforming part of the base 1, is also mounted a bottom bearing '7, andwithin the upper portion of the same housing is rotatably mounted anupper head 8 upon the motor shaft 9. The conductors to the motor areomitted for clarity, inasmuch as they are, of course understood to beconnected thereto through the housing to supply current, and likeremarks refer to the starting and running switch, also superuous toillustrate. The vertical motor shaft 9 carries a rigidly xed hollowcone-shaped cam 10 having a continuous double looped groove lll upon theexterior surface thereof in which a follower finger 12 slides. Thisfollower finger is securely xed upon one end of a long arcuate needlehar driving link 13 located within the hollow arcuate arm 2 and in theupper far portion of this arm having an offset reinforced part 42 with alimited longitudinal slot 43 through which a stationary guide member i4secured in arm 2 extends slidably to ensure that link 13 is supportedmovably in the same general position.

Midway up within arm 2 is pivotally mounted a forked arm 15 upon a pivotpin or stud 44 with the transverse pin 45 in link 13 located in the slot46 in arm 15. The latter arm may be resiliently mounted or have one ormore springs engaging with it to provide resilient resistance tomovement of the arm on its pivot 44 and thus prevent undue movement oflink 13 except as positively provided by the follower 12 riding in camgroove 11 during rotation of conical cam lll by motor shaft 9.

At the offset or elbow 42, the arm continues as an olfset needle bar i6which virtually forms one end of the cam and follower driving link i3,while the other end 17 of the link is directly connected to followermember 12 within housing 3. To the end of needle bar 16 is connected aneedle 18 adapted to be brought down between the feeding members 4already referred to, by longitudinal oscillation of link i3 and bar 16caused by rotation of cani lll. ln order to guide the needle iS andprevent outward misoperation thereof during the running of the machine,a guide roller or wheel i9 is mounted rotatably on the operating end ofarm outside end S. As may be noted in Figure l, the needle 13 has aslight curvature corresponding to the curvature of hollow arm 2, and maybe triangular in cross section, if desired and lit into a correspondingtriangular groove in needle bar i6, and a pin or set screw may be addedto further secure it in place, if desired.

ln the upper portion 47 of the mechanism housing 3 supporting upperbearing 8 is also supported a bobbin carrier 20 containing a specialbobbin 21, and, as best seen in Figure 4, the thread is provided to thesewing Zone through the opening or gap 4S of carrier 2t) and drawn frombobbin 21 to mesh with the thread coming down from needle 18, the bobbinrotating about a vertical axis in carrier 20 when the thread iswithdrawn during sewing. For the needle thread supply is provided a stud35 upon the near side of the upper portion of arm 2 upon which a supplyspool may be mounted, while a thread puller or feeder adjustment 34 ismounted on the elbow or offset 42 of link 13 and extends through a slot49 in the wall of arm 2 to the outside into accessible position on thearm. A thread tensioning device 33 is fixed on the arm 2 near the end 5thereof for the thread, which is led through the thread guide loop 32 onthe offset 42 and extends out through a slot Si) upon arm 2.

A presser foot 36 extends down toward feeders 4 and within arm 2 isconnected to needle bar 16, a manual lever 37 also extending into thearm 2 and connecting with bar 16 for manually adjusting and moving thebar when desired, it being evident that the presser foot extendsslidably through end 5 which serves as a bearing for the same. Upon theshank of the presser foot is fixed a transverse pin 51, while upon thisshank is also mounted a compression spring 52 working against a stop 53fixed on bar 16 which slidably supports the presser foot 36, to balancethe movement of the presser foot with bar 16.

Within the upper portion of cone cam 1i) is a socket 54 in which isloosely mounted a flanged rotatable shell 38 held downresiliently by aspring 55 mounted on shaft 9 between the upper head 8 and the bottom ofshell 38, so that the latter would normally tend to rotate with the Cone10 by friction. In upper portion 47 of housing 3, that may be a metalcasting, is rotatably mounted a vertical shaft 39 upon the lower end ofwhich is fixed a iiange or wheel 40 with an inclined or beveled edgecapable of frictionally engaging with the beveled edge or flange ofshell 38 and be rotated thereby to form an upper rotary vstop therefor.During operation, spring 55 tends to raise `head 8 into frictionalcontact with the underside of stitch forming shuttle to rotate thelatter and cause it to cooperate with needle 18 to form a stitch.

Within the side wall of housing 3 is mounted a pivot mounting 26 uponwhich the end of a lever 25 is pivoted so that its other slotted end 27may swing up and down as caused by a transverse pin 56 in the end 17 ofdriving link 13. An upwardly extending arm 29 is rigid with lever androcks therewith on pivot 26 and engages against an inclined cam portion31 by its upper end 30, this cam portion being fixed upon and disposedat right angles to a movable feeder plate 22 upon which the feeders 4are fixed, whereby a reciprocating movement is imparted to the feeders.This plate 22 is supported upon an upright arm 23 that is slidablysupported at its lower end upon a post 24 having guide flanges S7, 57for guiding arm 23 in movement. The upper plate 22 is guided by adepending rib 59 upon the underside of housing top S8 for to and fromovement provided by the cam 31 being engaged by end of arm 29 of lever25 which rocks with the movements of link 13 with follower 12 in groove11 on cone cam 10. This groove, as best seen in Figure 4 has a low loop60 and a high loop 61 which are both traversed in succession by follower12.

In an intermediate portion of upright arm 23 is mounted a pivot member28 operating in a slot 62 in lever 25 in such manner that independentlyof the fore and aft movement of the plate 22 and feeders 4 thereonprovided by arm 29 with cam 31, the plate with feeders 4 will also beslightly raised and lowered by the rocking of lever 25 on its pivot 26when raised and lowered at its slotted end 27 by pin 56 at follower 12.

The machine may be provided with a control knob 41 on arm 2 which mayhouse a starting switch operated by knob 41, if so desired, or any otherarrangement may be used for controlling operation of motor 6 and themachine as a whole.

From the foregoing, it is evident that the invention provides a largegap or throat of substantially circular form within the outline of arm 2for handling large pieces of goods and various shapes and sizes thereof.It is also evident that there is no complicated or clumsy operating headinvolved because the mechanism as a whole is almost entirely located inthe lower housing 3, and the mechanism is more compact and also moresimple in construction and nature than conventional sewinginstrumentalities. The view of the fabric being sewed is more exposed tothe eyes of an operator than on conventional machines, likewise, due tothe absence of the usual sewing head. The whole machine may thus restdirectly upon a table or similar support, and is very simple to operate.

Manifestly, variations may be resorted to, and parts and features may bemodified or used without others within the scope of the appended claims.

Having now fully described my invention, I claim:

1. A table sewing machine including a base adapted to rest on a table orother support, a substantially circular hollow arm rigidly mounted uponthe base and having a gap forming a sewing zone above one end of thebase, a motor drive located at said one end of said base, a housing uponsaid end of said base and enclosing the motor drive, a rotatable cammounted to rotate about a vertical axis and driven by the motor drivewithin the housing, the hollow arm terminating at the gap forming thesewing zone above said housing, a needle bar longitudinally reciprocablewithin said arm `toward and away from the sewing zone, a followerco-operating with said cam in said housing, an arcuate operating linkconnected at one end to the follower and extending movably throughoutthe greater portion of the hollow arm and at the other end beingconnected to the needle bar, and a presser foot movably connected to theneedle bar having resilient means located between a portion of saidneedle bar and said presser foot causing the presser foot to bearresiliently on the fabric at the sewing Zone when the needle proceeds topenetrate said fabric.

2. A sewing machine according to claim 1, wherein the cam is a coneshaped rotary continuous cam having a cam groove about the externalsurface thereof, the follower operatively engaging with the cam grooveto cause movement of said follower, and wherein the upper portion of thehousing has a support with a bobbin carrier and thread bobbin movablymounted in the said bobbin carrier, said bobbin carrier being mountedupon said support above said cam.

3. A sewing machine according to claim 2, wherein a thread tensioningdevice is mounted on the arm adjacent to the gap above the sewing zoneand the operating link at its junction with the needle bar has anoutwardly projecting thread guide loop extending to the outside of thehollow arm and also has a thread puller or feeder mounted thereonlikewise extending externally on the hollow arm in accessible positionfor positioning the thread, while a spool support is fixed upon anintermediate portion of said hollow arm for supply of thread for theneedle, tensioning device and thread loop.

4. A sewing machine according to claim 3, wherein the hollow arm at anintermediate position has a pivotally mounted forked arm therein and thearcuate operating link has a corresponding pin engaging transversely inthe forked portion of said forked arm, and resilient means mounted insaid hollow arm in contact with said forked arm for resilientlyresisting rocking of Said forked arm by movement of said operating link.

5. A sewing machine according to claim 3, wherein a transverse pin isiixed on the operating link adjacent to the end connected to the camfollower, and a lever is pivotally mounted at one end within the housingwhile the other end has a slot to engage with said transverse pin 75, torock the lever during rotation of the cam, and wherein a feeder plate ismovably supported Within said housing and feeder means extend upon theupper portion thereof exposed at the sewing zone beneath the needle andpresser foot, a side cam of inclined form being Xed on said plate, andwherein an arm is fixed on the lever at its pivoted end engaging againstthe inclined cam on said plate to shift the same with its feeder meansto and fro beneath the presser foot during operation.

6. A sewing machine according to claim 5, wherein a depending portionextends from the feeder plate and a t,

sliding support located in the housing, while a pivot member is disposedon the depending portion of the feeder plate and the operating lever hasa corresponding slot with which said pivot engages in order to raise andlower said plate with the rocking motion of said lever caused l bymovement of the operating link and follower when the cone cam rotates.

7. A sewing machine according to claim 6, wherein an upwardly opensocket is mounted upon the cone cam, a

flanged shell loosely mounted in the socket, a spring in contact withand urging said shell down into said socket, a vertical shaft rotatablein the upper portion of the hous ing, a flange on the lower end of theshaft frictionally engageable with the upper edge of said shell ineffective position to be rotated thereby to form an upper rotary stopfor said shell, and wherein a head is mounted upon the motor drive shaftabove said shell and albove the spring in effective position to beraised during operation by said spring into frictional contact with theunderside of the thread carrier to rotate the same about a vertical axisand actuate it effectively to co-operate with the needle to formstitches.

References Cited in the le of this patent UNITED STATES PATENTS

